Regioselective syntheses of new tri- and tetrasaccharides from β-glucobioses by Trichoderma viride β-glucosidase and their structural analyses by NMR spectroscopy
作者:Hiroyuki Kono、Markus R. Waelchili、Masashi Fujiwara、Tomoki Erata、Mitsuo Takai
DOI:10.1016/s0008-6215(99)00166-4
日期:1999.9
and gentiobiose into β- d -Glc-(1→6)-β- d -Glc-(1→3)- d -Glc (15.3%) and β- d -Glc-(1→6)-β- d -Glc-(1→6)- d -Glc (20.2%), respectively. The structures of the products were determined by 1 H and 13 C NMR spectroscopy. This high regio- and stereoselectivity demonstrated by the enzyme could be applied for oligosaccharide synthesis in general.
Transglycosylation of cellobiose by partially purified Trichoderma viride cellulase
作者:Hiroyuki Kono、Markus R Waelchli、Masashi Fujiwara、Tomoki Erata、Mitsuo Takai
DOI:10.1016/s0008-6215(99)00105-6
日期:1999.6
A commercial cellulase from Trichoderma viride was fractionated into three fractions, F1, F2, and F3, in order to investigate transglycosylation activities. Among these fi actions, F3, which demonstrated highly hydrolytic activity toward p-nitrophenyl P-D-glucopyranoside and Avicel, most effectively catalyzed the transglycosylation of cellobiose and converted cellobiose into beta-Glc-(1 --> 6)-beta-glc-(1 --> 4)-Glc and beta-Glc-(1 --> 6)-beta-Glc-(1 --> 6)-beta-Glc-(1 --> 4)-Glc. The F3 fraction contained the enzyme to catalyze beta-glucosyl transfer toward only the C-6 position of the sugar acceptor, and thus it is expected to be of use for syntheses of functional oligosaccharides. (C) 1999 Elsevier Science Ltd. All rights reserved.
Regioselective Syntheses of New Tri-and Tetrasaccharides by Transglycosylation of Trichoderma Viride β-Glucosidase
A new beta-glucosidase, which was partially purified from Trichoderma viride cellulase, catalyzed a transglycosylation reaction of cellobiose to give beta-D-Glcp-(1-->6)beta-D-Glcp-(1 --> 4)-D-Glcp 1 and beta-D-Glcp-(1 --> 6)-beta-D-Glcp-(1 --> 6)-beta-D-Glcp-(1 --> 4)-D-Glcp 2, regioselectively. Furthermore, the enzyme converted laminaribiose and gentiobiose into beta-D-Glcp-(1 -->6)-beta-D-Glcp-(1 --> 3)-D-Glcp 3 and beta-o-Glcp-(1 --> 6)-beta-D-Glcp-(1 --> 6)-D-Glcp 4, respectively. Selective beta-(1-->6) transglycosylation was achieved.